Seismic Performance Evaluation on Eccentrically Brace Steel Frame by Capacity Spectrum Method

According to the seismic demand spectra form the code for seismic design of buildings, seismic performances of eccentrically braced steel frames (EBF) in frequently, fortification and seldom occurred different intensity earthquakes were evaluated by the Capacity Spectrum Method (CSM). The capacity curves derived from base force-top displacement curves of structures subjected to the lateral seismic load of seismic codes were obtained from pushover analysis by applying sap2000 software and transformed to the spectrum curves, seismic performance were evaluated according to the intersection between the seismic demand spectra and the capacity spectrum. Seismic performances of 15 EBFs designed according to the Chinese design codes were evaluated by CSM. The certain ductility and displacement capacity of EBF in accordance with the China corresponding design codes are shown and some reference is suggested.